Recently, there are various kinds of known testing instruments for determining optical signal. Its principle is that the optical signal picked up or determined by a photo electric converter (transducer) is converted into voltage or current signal and then these voltage and current signal is amplified. With the quantum physics developing, a novel high-sensitivity photoelectric testing device so called a single-photon counting device has been manufactured and widely used in aviation, space-flight, military affairs, medical treatment, security, scientific research, environmental protection, agriculture, and industry etc. An example of applying a single photon counter in medical field is a micro-cellular-plate-single-photon counting device with it, widely applied in various aspects of the clinic diagnosis, such as gene analysis, determinations of hormones, medicines, vitamin, and materials related to cancers and infections. Generally, the micro-cellular-plate-singe-photon counting device is consisted of a probe; more than one test cell; a transporter mechanism carrying the test cells; a housing; a controller; a central computer. The sequential steps of the determination process of the micro-cellular-plate-single-photon counting device are below: putting the prepared sample into a test cell and then placing the test cells into sample container (namely, micro-cellular-plate, e.g., a micro-cellular-plate with an array of 12 rows by 8 columns of test cells, i.e. 96 test cells); putting the sample container, i.e. the micro-cellular plate, onto a bracket; covering the housing; delivering the bracket with the micro-cellular plate on it into the housing in a light-sealing state by the transporter mechanism when the device switch is turned on; and determining the samples in the test cells one by one by movement of the optical pickup of the counting device in relation to the sample container.
Since the micro-cellular plate single photon counting device is an instrument which determines the number of photons within the test cell, the light-sealing of the device must conform to a severe requirement.
The probe used in the prior art is shown in FIG. 17. FIG. 17 shows the relationship of the optical pickup 1 and a plurality (e.g. 96) of the test cells 6 arranged one by one integrally or put into a contiguous relation on the 96-site micro cellular plate during one of the sample being determined. The test cells are disposable plastic products. The flush of their mouths is poor and also fluctuations of the height exist among plurality of the test cells, which can cause a light cross interference between the determined samples(namely, a secondary light seal defect). Said light cross interference refers to that the optical pickup is influenced by the light from the adjacent test cells, leading to an error in the determination of the sample being detected since the top of the test cell being detected or the top of its adjacent test cells can't closely abut against the top plate 102 of the housing due to the poor flush and the fluctuations of the heights of test cells. The determining results can be substantially influenced especially when the strength of light from the samples of the adjacent test cells is relatively high while that of the sample being detected is relatively low.